The present invention relates to a display panel, and more particularly to the art of a display panel for use on an information processing device or the like, the display panel having a liquid crystal panel, a light guide plate, and a tablet sensor board.
Information processing devices such as personal computers or the like have a computer unit and a display unit including a keyboard and a display panel.
Some display panels have a liquid crystal panel and a light guide plate for guiding light from a light source to the liquid crystal panel that is controlled by a liquid crystal driver circuit. Some information processing devices allow the user to use an input stylus to enter characters, figures, etc. via a display panel. The display panel of such an information processing device has, in addition to a liquid crystal panel and a light guide plate, an electromagnetic-induction-type tablet sensor board mounted on a surface of the liquid crystal panel remote from the light guide plate.
In the conventional display panel with the tablet sensor board, a liquid crystal driver circuit board with a liquid crystal driver circuit mounted thereon is disposed directly behind the liquid crystal panel. Therefore, it has been customary to assemble the display panel by temporarily rolling up the liquid crystal driver circuit board, placing the tablet sensor board, positioning the tablet sensor board with respect to the light guide plate, and then attaching the tablet sensor board to the back of the light guide plate with an adhesive tape.
However, because the liquid crystal driver circuit board is temporarily rolled up, the tablet sensor board is then placed, and a dedicated jig is used to position the tablet sensor board, the assembling process is tedious, time-consuming, and inefficient.
Using the jig to position the tablet sensor board is problematic in that the positioning process is liable to cause positioning variations and the tablet sensor board tends to be positioned with unreliable positioning accuracy.
Furthermore, inasmuch as the tablet sensor board is manually attached using the adhesive tape, the assembling process is time-consuming, making it difficult to mass-produce the display panel. In addition, the installed tablet sensor board is apt to be displaced out of position when the adhesive tape is degraded due to aging or temperature changes.
It is an object of the present invention to provide a display panel which can be assembled with increased efficiency and has a tablet sensor board positioned with increased accuracy.
According to an aspect of the present invention, there is provided a display panel comprising a thin sheet-like panel energizable by a driver circuit for displaying information, a holding member holding the thin sheet-like panel in covering relation to at least a portion of a rear surface of the thin sheet-like panel, a first edge positioning rib projecting from a rear surface of the holding member remote from a front surface thereof which holds the thin sheet-like panel, and extending along one edge of the holding member, a second edge positioning rib disposed on the holding member and extending along an opposite edge thereof remote from the first edge positioning rib, and a sheet-like electromagnetic-induction-type tablet sensor board held on the rear surface of the holding member by the first edge positioning rib and the second edge positioning rib.
With the above arrangement, no dedicated jig needs to be used to position the tablet sensor board, and the tablet sensor board is attached to the holding member by being inserted into an installation space defined by the inner surface of a circuit attachment plate on which a liquid crystal driver circuit board is mounted. Therefore, the tablet sensor board can be positioned with highly reliable positioning accuracy, and the display panel can be assembled with utmost ease.
Inasmuch as it is not necessary to use an adhesive tape to attach the tablet sensor board to the holding member, the display panel can be assembled easily in a short period of time. Thus, the display panel can be mass-produced, and the tablet sensor board is free of undesirable positional displacements which would otherwise occur when the adhesive tape would be degraded due to aging or temperature changes.
Furthermore, the holding member may be molded of a resin material, and hence it may not obstruct or impair the magnetic field that is generated when the operator enters data with an input stylus, thus allowing the operator to enter data appropriately through the display panel.
The above and other objects, features, and advantages of the present invention will become apparent from the following description when taken in conjunction with the accompanying drawings which illustrate a preferred embodiment of the present invention by way of example.